1. Field of the Invention
The present invention relates to an electronically surveying apparatus capable of displaying a model of an object which is expected to be arranged at completion (expected arrangement at completion of an object) of, for example, engineering works, on a display screen based on design data.
2. Description of the Related Art
Heretofore, there has been known an electronically surveying apparatus, for example, as disclosed in JP-A 2002-202126, which is provided with a telescope portion for viewing an object to be measured, an imaging portion for imaging the measurement object viewed by the telescope portion, a displaying portion for displaying the measurement object imaged by the imaging portion on a screen as a real image, and a storing portion for storing design data which correspond to the measurement object.
Meanwhile, engineering works such as a civil engineering are carried out based on design data. For example, based on the design data, roads are constructed and finished to be in a predetermined configuration by building of an embankment and performing of cutting in a roadwork, and groundwork and construction of a building are carried out in a construction work. In these engineering works, surveying data are collected while viewing the measurement object with the telescope portion of the electronically surveying apparatus, and the collected surveying data and the design data are then compared in every management point to confirm whether or not the work is carried out according to the design data, in mid-course of an operation of the work. However, the management points do not necessarily represent the design data.
In addition, it takes a too long surveying time to judge whether or not the work is carried out according to a construction plan by comparing the surveyed data with the design data in every management point, and thus not only the surveying operation is cumbersome, but also it causes the work to be delayed.
Furthermore, it is difficult to image a positional relationship between an arrangement of an object according to a design and that of an object in an actual condition, since an existing building or a mark which becomes as a standard is not constructed in an early stage of the construction. Particularly, installing of slope stakes takes a long time and thus they cannot be piled efficiently, if a completed form of the object has not been imaged. Accordingly, a skilled worker such as a stake-installation craftworker is required for installing the stakes.